Important Trig Identities For Calculus III

There are three trig identities that will be seen consistently throughout Calculus III. These are must have tools when working with integrals calculating volume in both two and three dimensions. Having these functions memorized can mean of the difference between passing and failing tests, quizzes, and homework. Take the time to memorize these trigonometric identities and you will be one step further in passing Calculus III

Pythagorean Identity

1. cos^2(x)+sin^2(x)=1

Half Angle (Power-Reducing) Formulas

1. sin^2(x) = [1-cos(2x)]/2

2. cos^2(x) = [1+cos(2x)]/2

Happy Calculating!

-Dylan Miller